KiCad - A Cross Platform and Open Source Electronics Design Automation Suite
ANSYS Fluent - ANSYS engineering simulation and 3D design software delivers product modeling solutions with unmatched scalability and a comprehensive multiphysics foundation.
Proteus PCB design - Proteus PCB design combines the schematic capture and ARES PCB layout programs to provide a...
OpenFOAM - OpenFOAM® - Official home of The Open Source Computational Fluid Dynamics (CFD) Toolbox.
QUCS - Qucs, briefly for Quite Universal Circuit Simulator, is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit.
MATLAB - A high-level language and interactive environment for numerical computation, visualization, and programming